This invention relates to a latching relay; more particularly, to a contactless latching relay utilizing a Hall effect device.
The invention provides a way to make a contactless Hall effect switching device into a relay which will retain its switch orientation until deliberately changed. In commercially available Hall effect switching devices, a Hall element is provided together with circuitry to effect a switching function. These prior art devices are further provided with signal conditioners which include, as a minimum, a step function generator with hysteresis. Thus, a Hall effect switching device is provided with a positive ON or OFF level in the middle of a step as an aid to positive operation of the switch function; and, with sufficient spacing between the ON and OFF level to eliminate problems from small variations of the actuating signal.
The prior art also includes a latching magnetic relay in which the Hall effect sensor is combined with an integrated circuit and requires a south pole to operate it and a north pole to release it. However, these devices are relatively expensive. What is required is a simple and inexpensive device which may be readily converted to latching operation.